condition mean min max ZT0-3 35.411625 34.56445 36.2588 ZT4-7 34.845349999999996 34.845349999999996 34.845349999999996 ZT8-11 23.5098 23.5098 23.5098 ZT12-15 0 0 0 ZT16-19 29.617350000000002 29.617350000000002 29.617350000000002 ZT20-23 40.4533 40.4533 40.4533